Remove no longer required ignore_column calls

ee/app/models/ee/namespace.rb

@@ -21,10 +21,6 @@ module EE
     }.freeze
 
     prepended do
-      include IgnorableColumn
-
-      ignore_column :plan
-
       belongs_to :plan
 
       has_one :namespace_statistics

ee/app/models/ee/project.rb

@@ -7,13 +7,10 @@ module EE
     extend ActiveSupport::Concern
 
     prepended do
-      include IgnorableColumn
       include Elastic::ProjectsSearch
       prepend GeoAwareAvatar
       prepend ImportStatusStateMachine
 
-      ignore_column :sync_time
-
       before_validation :mark_remote_mirrors_for_removal
 
       after_save :create_mirror_data, if: ->(project) { project.mirror? && project.mirror_changed? }